Locking-type switch-operating handle



Filed Nov.` 3, 1927 '7 Sheets-Sheet I ,alf/7655,' /f

Sept. 2, 1930. A. ALsAKER Er AL 1,774,540

LOCKING TYPE swITcH OPERATING HANDLE Sept. 2, 1930. A. ALsAKER ET ALLOCKING TYPE SWITCH OPERATING HANDLE Filed Nov. 3, 1927 '7 Sheets-Sheetl i .3/ l I UHU/H? A 1 1 l T S2M/3 m 'bag Sept. 2, l1930. A. ALSAKER ETAL. 1,774,540

LOCKING TYPE SWITCH OPERATING HANDLE Filed Nov. 3, 1927 7 Sheets-Sheet 4l @d fa Sept. 2, 193D. A. ALsAKER ET AL LOCKING TYPE SWITCH OPERATINGHANDLE Filed Nov. 3, 1927 7 Sheets-Sheet 5 V 7- %fe" 75 ya 105 Ycnvenz'w I 1 d! red L#sa er @fa-55, E'fc ./Vardem Mm @M Sept. 2, 1930.A. ALsAKER ET AL 1,774,540

LOCKING TYPE SWITCH OPERATING HANDLE Filed Nov. 3y, 1927 7 Sheets-Shea?5 Eric /VOrCZ/em LOCKING TYPE SWITCH OPERATING HANDLE Filed Nov. 3, 1927'7 Sheets-Sheet 7 Patented Sept. 2, 1930 UNITED STATES ALFRED ALSAKERAND ERIC NORDHEM, OF CHICAGO, ILLINOIS, ASSIGNORS TO THE DELTA STARELECTRIC COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 0F ILLI- Nors'LOCKING-TYPE SWITCH-OPERATING HANDLE Application led November 3, 1927.ASerial No. 230,760.

rThis invention relates to switch operating means, and more particularlyto a handle adapted for connection to a switch remote from the handlethrough a suitable system of links and levers, means being provided foriocliing the handle in any one of several sefected positions.

Uur invention has to do primarily with the locking means for securingthe handle struc ture in adjustment. By our invention we provide a keyoperated lock and means associated therewith whereby the handlestructure can be positively locked against operation so as toeifectually prevent unauthorized opening or closing of the switch. Inconjunction with the locking means we also provide, in one form of thedevice, electro-responsive means for preventing release of the handlestructure by operation of the key operated lock until such time as theoil switch, or other apparatus used for interrupting the line currentand situated remote from the disconnect switch which is operated by thehandle structure. has been opened. After this has been done, theelectro-responsive means is actuated to permit release of `the handlestructure for closing or opening"- the disconnect switch. We alsocontemplate a further modification in which air-auxiliary switchcontrolling one or more` interlocking or signalling circuits isconnected to the lock controlled means in such-manner that the conditionof the disconnect switch operated by the handle structure will beproperly indicated at a point remote from the handle structure, and thefact that the handle is to be operated for closing or opening the disconnect switch will be signified at such point before operation of thehandle structure actually takes place. Further objects and ad vantageswill appeal' from the detailed description.

In the drawings Fig. 1 is an elevation of a handle structure inaccordance with our invention;

is a side View of the'handle struc in section Fig. 5 is a horizontalsection through the j handle structure and arm and the support-r ingbase;

Fig. 6 is a section taken substantially on line 6-6 of Fig. 4, on anenlarged scale;

Fig. 7 is a transverse section through the supporting base taken in theplane of the lock and the locking cam member, parts being shown inelevation;

Fig. 8 is a. transverse sectional view through the switch housing takenadjacent the upper end thereof and looking down;

Fig. 9 is a section taken substantially on line 9 9 of Fig. 8;

Fig. 10 is a section taken through the auX- iliary switch structuresubstantially on line 10-10 ot' Fig. 9; 1

Fig. 11 is a section taken substantially on line 11--11 of Fig. lt);

Figj12 is a section taken substantially on line 12-12 of Fig. 10;

Fig. 13 is a section through the supporting base and associated partsshowing the stop elements for preventing and limiting entry of the pawlinto the apertures of the hub of the handle member, the auxiliary switchand associated parts being omitted;

Fig. 14 is a perspective detail of one of the pawl limiting member-s;

Fig. 15 is a vertical vcentral sectional View through the supportingbase and associated parts from front to back of the base, illustratingthe second modified form, parts loeing shown in elevation;

Fig. 16 is a side view of the form of operating handle structureillustrated in Fig. 15;

Fig. 17 is a section taken substantially on. line 17-17 of Fig. 16; Y

Fig. 18 is a section taken parallel to and adjacent the cover of theelectromagnet housing in the form shown in Fig. 15, the base being shownragmentarily;

Fig. 19 is a vertical central sectional view through the lower portionof the base and the electromagnet housing, parts being shown inelevation:

Fig. 2() is a section through the electromagnet housing and associatedparts taken substantially on line QO-QO of Fig. 1S;

Fig. Z1 is a diagram showing the lock actuated switch connected tocontrol an oil switch, the signalling circuits controlled by tlieloc'kswitch being omitted for clearness; and

Fig. 22 is a diagram of the connections for the electromagnetic lockused in the switch illustrated in Figs. 15 to Q0.

The device includes a base member' 1 having a flange Q secured by meansot cap screws 3, or in any suitable or preferred manner, to a basemember or block adapted to be secured to a wall support in any suitablemanner. Base member 1 is provided in each side thereof, with a forwardlyprojecting standard 5 carrying a bearing sleeve G. A lshort length ottubing forming a shaft 7 is rockably mounted through the bearings 6 andprojects beyond the same to one side ot base member 1. in operating arm8 is secured on the projecting portion of shaft 7 by means of U-bolts 9and set screws 10. This arm is bifurcated to receive one end of a curvedlink 11 pivotally secured between the members of arm 8 by a pin 1Q heldagainst endwise movement by cotter pins, or in any other suitablemanner. Operating arm 11 is provided at its other end with a socketmember 13 in which is secured an operating rod 1-1, the other end ot`which is connected, in any suitable manner, to a suitable system oilinks and levers for operating a. disconnect switch disposed at a pointremote trom the operating handle structure. By rocking the shaft 7 aboutits axis into its extreme position iu either direction, the switch canbe easily opened or closed, as required.

Shaft 7 is operated by a handle structure This structure includes a rodor shank 1G provided at its upper end with a spade handle 1T. A hub 1Sis provided at the lower end of shank 1G. this hub having a socketmember 19 in which the shank 1G is secured by rivets '2O (Fig. or iu anyother suitable manner. The huh 18 is bored and threaded.v adjacentsocket member 19. for reception of dog point set screws 21, the pointsot which enter corresponding openings in shaft T. This serves toeiiectually secure the handle structure to the shaft tor operating .thelatter.

adapted for reception of a nose element 23 of a holding pawl 24 rockablymounted on a pin Q5 extending transversely ot the base 1 above shaft 7.1t will be noted that the openings 22 are of approximately segmentalshape and converge inwardly of the hub, the element Q3 being shapedlsimilarly to the opening and of somewhat less width. This renders itpossible to force element Q3 out of the opening 2:2 when the pawl 2-1 isreleased by exerting appreciable pressure on the contacting inclinedsurfaces ot' element 23 and the wall of opening 22 with which thiselement contacts. It will thus be seen that, when the pawl is released,the hub 18 can-die turned into either position desired by firstreleasing it from the pawl which may be readily accomplished by exertingaslight pull upon the handle 1T.

For locking the pawl 24 in holding or operative posit-ion 1 provide acam 2G trom one side of which extends a stub shaft QT which is rockablymounted in a tubular boss 2S projecting inwardly from one side of thebase member 1. This cam is positioned and adapted to be turned into andout of operative relation to a finger element Q9 extending from the freeend ot pawl 21. the lower portion of this element heilig provided withan arcuate recess for reception of the cam. Then the cam is in operativeposition, the pawl is effectually held against outward movement and isretained in operative positionuwith the element 23 disposed-in lone otthe openings '22 locking the hub. and, consequently7 shaft. T, inadjustment. By turning the cam into inoperative position the pawlisreleased and can be moved out of operative engagement with the hub inthe manner previously described.

A key operated lock 30 is mounted in the other side wall of the basemember 1. This lock includes` an outer fiange 31 and a. body 232 whichpasses through an opening in wall 1A, this body being provided, at itsinner end, with outwardly projecting diametrically opposite lugs 33. AU-shaped clamp 34 straddles body 212. this clamp being provided at theend of each arm with a rounded finger bearing upon the inner A pressurescrew 3C is 1 face of wall 1A. threaded through the bight portion ofthe, clamp and bears against the bottom wall ot a recess provided inwall 1A for reception of this screw. This provides simple and ei'iicientmeans for securing the lock in the base member.

The lock used is a standard make of Yale lock made by the Yale & TowneCompany. This lock is ot the cylinder type and includes a rotary barrelor cylinder 8T which projects inwardly beyond the inner end ot body 3Q,this cylinder receiving at its outer end the key. rotation of thecylinder when the key is withdrawn being prevented by the pins ortumblers of the lock in a known manner.

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. 49 at right angles thereto.

Cylinder 37 is connected to cam member 26 by a connecting rod 38. Thisrod 1s provided at one end with an L-shaped member 39, one arm of whichengages into a recess in cylinder 37'. An angle plate 40 fits about thelower portion of cylinder 37, as considered in Fig. 7, andis Secured tothe c linder by a screw 41. This plate" abuts the at surface of theouter arm of member 39 and serves to hold this member againstundesirable looseness or play. At its other end the rod 38 is providedwith a diametrically extending rib 42 from the central portion of whichprojects a reduced pin 43. Rib 42 ,fits into a groove 44 provided in theinner lface of cam 26 and the pin 43 extends into a recess or boreextending from the bottom of this groove. In this manner the cylinder-of the lock and the cam member 26 are operattively connected to etherso that the cam member will turn with the cylinder and will be securedby the cylinder against turning 'movement when the key of the lock iswithdrawn and the cylinder is locked against movement. The lock thusforms key operated means for operating and controlling the cam memberand, consequently.. the release and locking of the handle structure.

A coiled torsion spring 45 is mounted about rod 38 and is confinedbetween the cam and an ieye 49 of an arm 50 the other end of which fitsinto a groove in a pin 51 projecting laterally from pawl 24 (Fig. 4 andFig. 6). A finger 52 extends inwardly from eye This finger is providedin its inner edge with a notch (Fig. 5) which receives one end of thetorsion spring 45. The other end of the spring engages about a pin 53projecting inwardly from the inner face of cam 26. By reference to Fig.3 it will be seen that the torsion spring urges the cam member in aclockwisedirection and the arm 50 in a counterclockwise direction so asto urge the pawl 24 toward hub 18. Movement of the cam in clockwisedirection will be limited by movement of the cylinder of the lock whichis not permitted to turn in such direction beyond full locking position.If desired, the cam member m'aybe provided with a stop element or pindisposed for contact with the terminal element 29 of the pawl forlimiting movement of the cam member in locking direction though, underordinary conditions, we do not deem this necessary. With the parts inthe positions shown in 3, the handle structure and shaft 7 are eectually held by the pawl 24 in switch closing position. When it isdesired to open the switch, the key is inserted in the lock and thecylinder thereof is turned in proper direction to turn the cam memberthrough an arc of approximately 180 degrees in a counterciockwisedirection, as considered in Fig. 3, releasing the pawl 24 and permittingmovement thereof away from the hub sufficiently to disengage element 23from its recess. After the hub has beenturned a short distance,'the keyin the lock may be released, as return of the pawl to locking positionwill be prevented by contact of element 23 with the hub. `lVhen theshaft has been turned into full switch opening position, the otherurecess or opening 22 of the hub is brought into alignment with element23 of the pawl which is then moved inwardly by the spring to positionelement 23 in the opening. This releases Fthe cam member which is thenreturned to locking position by the spring. In

this respect the locking mechanism is automatic in its operation in thatit is held inoperative during movement of the shaft from either of itsextreme positions to its other extremeposition, and is then actuated bythe spring to lock the shaft against movement. We have shown the hub 18as provided with a third recess or opening 22A midway between the twoopenings 22. This central opening may be employed whenever it is foundnecessary or. desirable, be-' cause of restricted space or for otherreasons, to lock the handle structure in substantially horizontalposition, that is, in position midway between its two extreme positions.W'hen it is not desired to use the opening 22A it may be closed orrendered inoperative by means of an arcuate closure plate 54 of a sizeto fit snugly in the outer portion of this opening, this plate beingsecured in position by a screw 55 passing therethrough and 1U;

threading into a clamping plate 56 disposed inside ot the body of hubv18 between the same and shaft 7. To accommodate this clamping plate thehub 18 is provided, at each end thereof, with an inwardly projectingflange 18A, these fianges and the body of the hub enclosing an annularspace 57 about the shaft. This structure will be clear from reference toFig. 5. At times it is desirable to provide means whereby the key cannotbe withdrawn from the lock except after the switch is closed. It is alsooften convenient to permit the key to remain in the lock, particularlywhen the switch is to be open but a short length of time, as thisprevents loss of the key and insures that it is readily available whenit is desired to close the switch. `With this object in view we providemeans whereby entry of the element 23 of pawl 24 into the opening 22 islimited. In

Figs. 13 and 14 we have illustrated a stop member including an arcuatebase 58 and a body 59 of a size to be inserted into the inner portion ofopening 22 from inside the hub. The base 58 corresponds in thickness tothe width of space 57 radially of the hub and is disposed concentricwith the shaft andl the hub. This member is applied before the hub ismounted on the shaft and is held in position by the shaft, as lwill beclear from i ecl xvi `i` i m eei'entrie o i'.

uf oi the umn in inciting; lieieniljif to loi-li the inurl againstoutward niowinent whie preventing turning o' the. ouin into t'nlloeking' position. This Serves to hiel; the hnh again@ niooinent 'neither direction and :11S-o prevents iif'ithdrzzwni ot the lier tronitheI lovl, it. being" 'd nierstofjic that the liey Cannot, hewitlnlrzin'n Yfrom th, loci; until the eyliiuler oi thel loi-l; has heentnrneil into i'nil locking position in zieeorclzinee with the eonnnonpractice in ioeks oi alf, type. wYhen it is desired to eioe the switch.the lock is operated to reieuse the piiWl mul the ininille s'ruenre isthen returned to Switch eiosin;r poeiiion, utter which the koi; isrelezisei'l zinil the Carin f etnrneil l the torsion spring to fulloperative or locui position,n after which the lief; nur,v 'ne n nirunntroni the leek.

.it is frequently fiesiruhle in notifyQ parties n suh-stution or sonicpnini remote from m'itrh. ot? the eonilition oi" the whether theyswitf'h i'loseii ig or open. it muy :liso he VIfound ileeirnhhtoi'liivifle menne for notifying' parties nt the iiiei'onnw switchoperzing iminlle oi the i ion oi the line zweiten. i'itli these ohinnien" ne eonteniplnte inirvifling in ont'olling Sign-ailing or inthi 4auxiiinry switrh he ieioei( operatori means i'or in. iv.

i' io Li iwill nienihe'.' or liiovi; sinh) liu nonne;

The Sii'iteh r..- eiiuie rertzingninr 'tranne il of nl isiilior-hronxeor other :nimble inuterinl. @un piniw: or elw-urli nieniiiere /i'ffim'nieii of vonnnerrizilli' suitfihle "or insuiuting inzittrizii. :ireseinreii to te ahh@ oi irine 7l hi' nro@ A ilu iilzztes. :imi threuilinginw the iii'iieneil eoi'nei's: of the. irsnne. Ain operati r ir:siiilzihl): mounted thronfgh the oniis of the frnnie Tl. the 'free enilportion i': of this roll heine rei'lneeil in iliznneter, :leilinf-lti'nteil in Fig. i?. nl '-i thiezitiw throngh the vent nl portionot i iiloel 3 oi' un):

snit- :ihie insulatingr iniiteriuh mui. es iiher. vl Synthetic resinknown @in hal-rente. hioel; in provided. :nijneent mieli e i hoi-eexieuiinjg through the bloei( troni fiile to iile thereof. short pin Tiother oleetrii'nl insulriting nniter hh' mounted in each bore :indivan-illy hy :in expansion eoii epi-ing T3, also mounted in the hore.The pins and the epringjs, are Confined between trio contact stripe Tf)of sonner or other suitable eietrieal eonfiiuting; ninterizih thesestrips seating in reitnngnlzir grooves 8O extending from front to hackof the interni tures of the nloek und interseetiingthe bores thereof.lach strip l') is provideci, in its inner tace :1nd adjacent eheh end.with ii recess Si, these recesses: ie-

izil is Sl'ilzieeiving the end portions of the pins 7T :1nd the springsT8 Which Seat therein, Movement ot the Contact strips 79 inlay from theblock 76 is positively limited hy the plates 72. The springs and thepins :iet to press` the strips outwurdly into Contacty with the platesTQ and also serve to liohi these strips ngninet endwise movement. ASwill he noted more. lean-ly from Fig. l2, the springs :nul the pins inthe bores o' the hloek are oppo- Sirely related so that each Contactystrip is held in position unil nrgeil outwardly by n nin :nifl u. springin direct engagement therewith.

plurality, in this ense four, of terminal plates 72. so that, uponmovement of the block 76 into its extreme position in either direction,two sets or pairs ot the terminal members are. connected electricallythrough the contact strips 79. This provides simple and efhcient meansfor controlling a plurality of interlocking or signalling circuits bymovement ot' the block 76. B v referring to Fig. 3. it. will be notedthat the switch operating rod 71 is connected bv a. link 86 to pin 53 otthe cam 20. When the handle structure is in position closing thedisconnect switch. the block 76 is raised and the coutact strips closethe proper circuits to signify this` fact. Then it is desired to openthe contact switch it is necessary to first unlock the holding pa wl 24by turning the cam member in a counterclockwise direction, as consideredin Fig. 3, through an arc of approximately 180 degrees. This movement ofthe cam member serves to move the block 76 into its lower positionclosing the circuits controlled bythe lower pairs or sets of terminalmembers andsignalling the v'intention to open the disconnect switch. If,for any reason, the disconnect switch should' not be opened, thisfactcan be signified by a suitable signal operated from a sub-stationorsome point remote from'the switch operating handle structure, .thissignalling means being included in one ofthe-circuits controlled by theauxiliary switch. In this connection it is important to note that thepawl 24 is not released until after the block 76 has been loweredsufficiently to connect the lower terminal members through the contactstrips 79. Movement of the insulatingy block in either direction islimited by abutment elements 87 adjacent the 'corners of frame 71. Thethreaded connection between the operating rod 74 and the block permitsof adjustment between these two members to obtain accuracy in operationot' the switch without interfering with the properoperation of the cam26, and the connectionsbetween the movable member'of the switch and thecam assure that the switch will be operated only at proper times and bya properly authorized person.

In Figs. 15 to 20 we have illustrated a moditied form in which theopening of the disconnect switch can be positively prevented from apoint remote from the operating handle structure. A. latch 88 is pivotedat one end at 89 on a. pin 90 projectingr from the lower wall of basemember 1. This latch is loosely connected at 91. to one end of a rod 92,the other end of which is secured to one arm of an L-shaped lever 93secured in a U-shaped stirrup 94 rockably mounted on a pin 95 extendingtransversely of a housing 96 secured to the lower end portion of basemember 1.

An electromagnet of suitable type is mounted within the housing 96. Thiselectromagnet includes a core formed of two substantially U-shapedmembers 97, the outer arms of which are secured by screws 98 to brackets99 secured by screws 100 to the inner wall of the housing. The innerarms of the members 97 are secured togetherv in any suitable manner asby riveting (Fig. 20) and these members form a core within which isdisposed the coil 101. The terminals of this coil are connected tobinding posts 102 carried by a cross bar 103 .of any suitable electricalinsulating material such as the synthetic resin known as bakelite, thisbar being secured between the side walls of the housing in any suitablemanner as by screws 104. A cover plate 105 is secured over the front ofhousing 106 by means of screws 107 passing through this plate andthreading into the members 97, this plate being provided with suitablydisposed flanges about its periphery lor properly positioning it. wellas the rod 92 and latch member 88 are preferably made of brass or othersuitable non-magnetic material, and an armature 107 of sott iron orother suitable magnetic material is secured across the lower end ofthelever 923 and is disposed adjacent and in alignment with the inner poleof the electro- The lever 93, as l magnet. The electromagnet is normallyenergized so as to hold the armature 107 in its raised or outerposition. This holds the lever in rocked position about its pin 95 anddisposes the bill 88A of latch member 88 in position for engagement witha pin 108 secured in cam 26 and projecting therefrom atthe same side asthe pin 53. `This pin 108 is so disposed as'to engage with the latchmember before the cam has been turned intofull unlocked or pawlreleasing position. It will thus be seen that it is impossible torelease the handle structure until the circuit through the coil of theelectromagnet is broken. This circuit is preferably so arranged that theelectromagnet is energized continuously as long as the line switch isclosed. This provides a very effective safety control which will preventopening of the disconnect switch until the line circuit has been brokenor opened.

In Fig.`2l we have illustrated diagrammatically the application of ouropera-ting handle and associated lock actuated switch lto a high tensionbus circuit the diagram being of the conventional one line type, thedisconnect switch being indicated as gang operated. When handle 15 israised, as indicated in dotted lines, the disconnect switch 110 isclosed, closing the bus circuit from bus 111 through wire 112 to the oilswitch 113, from which it extends to the load after the oil switch isalso closed. To open the disconnect switch it is necessary to firstoperate lock 72fto turn the cam 26 into inoperative position to releasethe pawl 24. This moves strip 79 into contact with the Contact members84. The circuit of the trip coil (not shown) of the Oil Switch iS thenClosed from the positive operating bus 114 through wire 115, strip 79,lead 11G. wire 11T. trip wire 118, the trip coil, and the common wire119 to the negative bus 120. This opens the oil switch before it ispossible to open the, disconnect switch, rendering it impossible to openthe disconnect switch under load. As the handle '15 reaches its fullswitch opening position, the contact strip TD is rcturned to raised orinoperative position. per mitting closing of the oil switch. Before thehandle can be returned to switch closing position it is necessary toagain operate the lock T2 closing the circuit of the trip coil of theoil switch as before and opening the oil switch before it is possible toclose the disconnect switch. It will thus be seen that, by the provisionof the lock actuated switch and associated parts, we provide simple andefficient means for preventing either opening or closing of thedisconnect switch under or on load.

An overloadrelay 121 is connected to the high tension 'bus wire 112through a suitable transformer in a known manner. This relay acts tonormally hold a contact strip 122 away from contacts 123 which areconnected in shunt with wire. 115 and about contact members 84. In theevent of an overload, the strip 122 is shit'ted into position to bridgethe contacts 123 closing the circuit of the trip coil of switch 113 frompositive bus 111 through wire 115. wire 11T and strip 122, trip wire 118tothe coil, and common wire 119.to the negative bus 120. As the overloadrelay is shunted around the lock actuated switch of the operatinghandle` it can operate at any time regardless of the. condition of thedisconnect switch.

Il control switch 124 is provided for opening and closing the oilswitch. When the control switch is on contact 125 the circuit of theclosing coil of the oil switch is closed from positive bus 114V throughwire 12C. closing wire 12T and the closing coil to thev common wire 119.and through wire 1151 to the negative bus 1211. rl`o open the oilswitch` cont-rol switch 12st is moved into contact- 12S trom whichextends trip wire 11F. rlhis closes the circuit ot the trip coil frompositive luis 111 through wire 126 and switch 124, trip wire 118. thetrip coil, and through the common wire 119 to the negative bus 1211.opening the oil switch.

Two pilot lights` one red and one green. as indicated. are connected inscrics with wire 126 and wires 118 and 12T. respectively. v'sllhenswitch 12J.- is open both of these lights are illuminated. theircircuits being closed through the trip coil and the closing coil.respectively. of the oil switch. ance of these lights is sntlicientlyhigh to preventr the. nov-r of sulficicnt current to 'tl coils tooperate the switch. as is well e stood in this e ilhen switch is in Theresistengagement with contact 125 for closing the oil switch. it shuntsthe green light which is thus extinguished. leaving only the red lightilluminated. Upon movement of switch 124 into engagement with contact1251 to open the oil switch, the red light is shunted. leaving only thegreen light on. These lights are suitably disposed to indicate to theoperator the condition of the control switch and, consequently, of theoil switch.

ln Fig. 22 the disconnect switch is shown as closed. The coil 101 of theelectromagnet is energized through the medium of a potential transformer130, the primary coil of which is connected at one end to wire 112, theother end of this coil, as well as the corresponding end of thesecondary coil, being grounded at 131. The other end of the secondarycoil of the transformer is connected to one end of coil 101 which hasits other end grounded at 132. When the oil switch is closed. theelectromagnet is energized preventing opening or closing of thedisconnect switch in the manner previously described. This rendersitimpossible to either open vor close the disconnect switch under oronload.

As above indicated. and as will be understood by those skilled in theart, changes in construction and arrangement of parts of our inventionmay be -.resorted to without departing from the field and scope of thesaine, and we intend to include all such variations. as fall within thescope of the appended claims. in this application-in which the preferredforms only of our invention have been disclosed.

llihat we claim ist- 1. ln switch operating means, a handle structureincluding a huh mounted for turning movement, a pawl, said huh and thepawl having co-acting means for locking the huh in adjustment, said pawlbeing biased to the locliing position. and cani means for rigidlyholding the pawl in the locking position.

ln switch operating means. a handle structure including a hub mountedfor turning movement, a switch operating arm having operative connectionwith the hub. a holding pawl adjacent the huh` said pawl and the huhhaving co-acting means for l'iolding the hub in adjustment. and means'for ioclting the. pawl against retraction 'troni the holding position.

2l. `ln switch operating means. handle structure including a hub mountedfor turning movement, a switch operating arm having operative connectionwith the huh, a holding pawl adjacent the huh. 'il pawl andthe huhhaving co-acting means `for molding th.l huh in adjustment. andlo/.dr-controlied means for locking the pawl against retraction from theholding position.

s1. ln switch operating' means. a

mounted shaft, a switch operating are.

cured on said shaft, a handle structure including a hub secured on theshaft and provided with spaced recesses. a holding member movable towardand away from the. hub and. having an element disposed to project intothe recesses of the hub for securing i't in ad justment about. its axisthe recess and the pawl being relatively shaped to exert an outwardforce on the pawl upon the application of pressure thereto by the huh,and lock con trolled means for securing the holding niember inoperative.

5. In switch operating means, a supporting base. a shaft rockahlymounted in the hase. a switch opeiating arm secured on said shaft, avhandle structure including a huh secured on the shaft and having spacedreL cesses, a holding pawl mounted in the hase and having an element.disposed to project into said recesses. said pawl'being urged toward thehub, and lock controlled means for locking the pawl in position in therecess.

(i. In switch operating means, a supporting hase, a shaft rockablymounted in the hase, a switch operating arin secured on said shaft, ahandle structure including a hub secured on the shaft and havingspacedreccsses, a holding pawl mounted on the base and having an elementdisposed to project into said recesses, said pawl being urged toward thehub and the element of the pawl being shaped to be forced out of the.recess by Contact with the wall thereof upon turning of the shaft ineither direction under appreciable pressure, and lock controlled meansfor securing the pawl in operative position.

7. In switch operating means, a support ing base, a'sliat't rockablymounted in the base, a switch operating arm secured on said shaft, ahandle structure including a hub secured on the shaft and provided withspaced recesses, a holding pawl disposed for engagement. into saidrecesses and urged toward the hub, a key operated lock, and a lockingmember operatedby the lock and movable thereby into and out of positionto hold the pawl in position in the recess.

8. In switch operating means, a supporting base, a shaft rockablymounted in the base, a switch operating arm secured on the shaft, ahandle structure including a hub secured on the shaft and provided withradially disposed recesses, a pawl mounted in the hase and having anelement. disposed for engagement into said recesses, the pawl beingurged toward the hub, a` cam meinbenmounted in the. base for movementinto and out ot' position to hold the pawl against retraction from thehub, a lock mounted in the base, and operating connections between thecam and the lock.

il. In switch operating means, a rockably mounted shaft, a switch armsecured on the shaft, a handle structure including a hub secured on theshaft and having recesses, a pawl yieldingly urged toward the huh andhaving an element. engageable into said recesses and shaped to be forcedout of the saine by contact` of the walls of the recess with saidelcineiit under appreciable pressure, a cam mounted and disposed formovement into and out of position to hold the pawl in operativeposition, and vielding means urging the cam into pawl holding position.

l0. In switch operating means, a rockahly mounted shaft. a switch armsecured on the shaft, a handle structure including a hub secured on theshaft and having recesses, a pawl yieldingly urged toward the hub andhaving an element engageable into said rccesses and shaped to be forcedout of the same by contact ot' the. walls of the recess with saidelement under 'appreciable pressure, a cani mounted and disposed formovement into and out of position to hold the pawl in operativeposition, yielding means urging the cam into pawl holding position, anda lock liav ing operating connection with the cam for moving it intoinoperative position and sceuring it. in operative position.

1l. In switch operating means, a roekably mounted shaft. a switch aiiiisecured on the shaft. a handle structure including a hub secured on theshaft and having recesses` a pawl having an element engageable into saidrecesses, means for optionally preventingr complete entry of saidelement into a selected one of said recesses, a cam mounted and disposedfor movement into and out of position to hold the pawl in operatingposition. a hey operated lock having a movable key receiving member, andoperating connections between said member and the cani.

1Q. In an electric switch, switch operating means, a pawl normally urgedinto a position to prevent the operation of the switch, said pawl being`retractable from said position rc.- sponsive to the attempted operationof said means, and key operated locking means for preventing theretraction of the pawl.

13. In an electric switch having a predetermined numhcr of selectivelyoperated positions, a pawl normally urged into a position to prevent theoperation of the switch from any one of the selective positions in whichit happens to be, said pawl heilig retractable from said positionresponsive to au attempted operation of said switch. said pawl beingineffective while the switch is in a position intermediate an operatedposition, and automatically effective upon the switch reaching anoperated position, and key operated locking means for preventing theretraction ofthe pawl. i

14. In an electric switch having a predetermined number of selectivelyoperated positions, and a number of spaced recesses, one for eachposition of the switch, a pawl normally urged into said recesses andretractable responsible to an attempted operation of the arms projectingfrom said base, bearin journaled in said arms, a shaft mounted 1n saidbearings, a disconnect switch operating mechanism connected to saidshaft and p- 5 erated thereby, a handle structure including a hubmounted on said shaft for actuating the same, cam means for preventingactuation ot' the shaft, means controlled by the handle for releasingthe cam means, electromagnetic means and separate key controlled meanscach controlling the release of said cam means by the handle.

27. A switch operating structure comprising a handle having a hubmounted for turning movement, a switch operating arm having operativeconnection with the hub, a ,i holding pavvl adjacent the hub, said pawland the hub having coacting means for holding the hub in adjustment andbeing shaped to force the pawl out of engagement with the hub upon theapplication of pressure thereto by the hub, and means for locking thepawl against retraction from the holding position by the hub. g5 28. Aswitch operating mechanism comprising a handle structure including a hubmounted for turning movement, a switch operating arm having operativeconnection with the hub, a holding pawl adjacent the 3o hub, said pawland the hub having coacting means for holding the hub in adjustment,said hub constituting means for retracting the pawl, and lock-controlledmeans for Securing the pawl against retraction from the holdingposition. E29. A switch operating mechanism conlprising a supportingbase. a shaft rockably f, mounted in the base, a switch operating armsecured on said shaft, a handle structure in- 4u cluding a hub securedon the shaft and having spaced recesses, a holding pawl mounted in thebase and having an element disposed to project into said recesses, saidpawl being urged toward the hub, and lock-controlled means for securingthe pawl in operative position, said recesses urging the pawl outwardupon the application of a turning force on the hub.

30. A switch operating mechanism comprisinga supporting base, a shaftrockably mounted in the base, a switch operating arm secured on saidshaft, a handle structure including a hub secured on the shaft andprovided with spaced recesses, a holding pawl disposed for engagementinto said recesses and urged out of engagement therewith by the hubstructure, said pawl being biased toward the hub, a key operated lock,and a locking member operated by the lock and mov- Wl able' thereby intoand out of position to hold the pawl in its operative position.

ln witness whereof, We hereunto subscribe our names this 9th day ofSeptember, 1927.

ALFRED ALSAKER. ERIC NORDHEM.

